Why do I receive the above error after installing SEE client
Symptoms
"An unsupported storage controller has been detected"
AHCI is enabled in BIOS and is not supported with the Symantec Endpoint Encryption Client
This issue is fixed for most hardware in SEE 7.03. Generally the error occurs on machines with a BIOS setting for hard disk operation set to AHCI. For Dell computers, this may be labelled "SATA Operation", and on HP computers this is usually listed as "SATA Native Mode", which would need to be disabled. After switching the setting to ATA or turning SATA Native Mode off, depending on the machine model, the system will start normally.
Various models of hardware have similar BIOS settings for hard disk operation, and in general, changing this from AHCI with whatever method available will resolve the issue.